Meta-analysis of the incidence and patterns of second neoplasms after photon craniospinal irradiation in children with medulloblastoma.

BACKGROUND: Second neoplasms (SNs) are a well-established long-term adverse effect of radiation therapy (RT), but there are limited data regarding their incidence and location relative to the radiation field, specific to medulloblastoma (MB) survivors after craniospinal irradiation (CSI). METHODS: A systematic literature review, per Preferred Reporting Items for Systematic Reviews and Meta-Analyses, identified six studies reporting the incidence and locations of SNs for 1,114 patients with MB, after CSI, with a median follow-up of ∼9 years (7.6-15.4 years). The study-specific cumulative incidence (CI) of SNs, second benign neoplasms (SBNs), and second malignant neoplasms (SMNs) were standardized to a 10-year time frame. Meta-analysis was performed using random effects models, with pooled data from selected studies and an institutional cohort of 55 patients. RESULTS: The 10-year CI was 6.1% for all SNs (excluding skin cancer and leukemia), 3.1% for SBNs, and 3.7% for SMNs. Fifty-eight percent of SNs were malignant; high-grade glioma was the most common SMN (15/33; 45%) and meningioma, the most common SBN (16/24; 67%). Forty percent of SNs occurred outside the target central nervous system (CNS) field, with a majority in areas of exit RT dose. Seventy-four percent of extra-CNS tumors (17/23) were malignant, most commonly thyroid carcinoma (7/17; 41%) and bone and soft-tissue tumors (6/17, 35%). CONCLUSIONS: Survivors of MB are at risk of SNs both within and outside the CNS. A significant proportion of SNs occur in areas of exit RT dose. Studies are needed to determine whether the use of proton therapy, which has no exit RT dose, is associated with a lower incidence of SNs

Low early ototoxicity rates for pediatric medulloblastoma patients treated with proton radiotherapy

<p>Abstract</p> <p>Background</p> <p>Hearing loss is common following chemoradiotherapy for children with medulloblastoma. Compared to photons, proton radiotherapy reduces radiation dose to the cochlea for these patients. Here we examine whether this dosimetric advantage leads to a clinical benefit in audiometric outcomes.</p> <p>Methods</p> <p>From 2006-2009, 23 children treated with proton radiotherapy for medulloblastoma were enrolled on a prospective observational study, through which they underwent pre- and 1 year post-radiotherapy pure-tone audiometric testing. Ears with moderate to severe hearing loss prior to therapy were censored, leaving 35 ears in 19 patients available for analysis.</p> <p>Results</p> <p>The predicted mean cochlear radiation dose was 30 ⁶⁰Co-Gy Equivalents (range 19-43), and the mean cumulative cisplatin dose was 303 mg/m²(range 298-330). Hearing sensitivity significantly declined following radiotherapy across all frequencies analyzed (<it>P </it>< 0.05). There was partial sparing of mean post-radiation hearing thresholds at low-to-midrange frequencies and, consequently, the rate of high-grade (grade 3 or 4) ototoxicity at 1 year was favorable (5%). Ototoxicity did not correlate with predicted dose to the auditory apparatus for proton-treated patients, potentially reflecting a lower-limit threshold for radiation effect on the cochlea.</p> <p>Conclusions</p> <p>Rates of high-grade early post-radiation ototoxicity following proton radiotherapy for pediatric medulloblastoma are low. Preservation of hearing in the audible speech range, as observed here, may improve both quality of life and cognitive functioning for these patients.</p

Pseudoprogression After Proton Therapy of Pediatric Spinal Pilocytic Astrocytoma and Myxopapillary Ependymoma

https://openworks.mdanderson.org/sumexp23/1025/thumbnail.jp

Proton Beam Therapy Versus Conformal Photon Radiation Therapy for Childhood Craniopharyngioma: Multi-institutional Analysis of Outcomes, Cyst Dynamics, and Toxicity

PurposeWe compared proton beam therapy (PBT) with intensity modulated radiation therapy (IMRT) for pediatric craniopharyngioma in terms of disease control, cyst dynamics, and toxicity.Methods and MaterialsWe reviewed records from 52 children treated with PBT (n=21) or IMRT (n=31) at 2 institutions from 1996-2012. Endpoints were overall survival (OS), disease control, cyst dynamics, and toxicity.ResultsAt 59.6 months' median follow-up (PBT 33 mo vs IMRT 106 mo; P<.001), the 3-year outcomes were 96% for OS, 95% for nodular failure-free survival and 76% for cystic failure-free survival. Neither OS nor disease control differed between treatment groups (OS P=.742; nodular failure-free survival P=.546; cystic failure-free survival P=.994). During therapy, 40% of patients had cyst growth (20% requiring intervention); immediately after therapy, 17 patients (33%) had cyst growth (transient in 14), more commonly in the IMRT group (42% vs 19% PBT; P=.082); and 27% experienced late cyst growth (32% IMRT, 19% PBT; P=.353), with intervention required in 40%. Toxicity did not differ between groups. On multivariate analysis, cyst growth was related to visual and hypothalamic toxicity (P=.009 and .04, respectively). Patients given radiation as salvage therapy (for recurrence) rather than adjuvant therapy had higher rates of visual and endocrine (P=.017 and .024, respectively) dysfunction.ConclusionsSurvival and disease-control outcomes were equivalent for PBT and IMRT. Cyst growth is common, unpredictable, and should be followed during and after therapy, because it contributes to late toxicity. Delaying radiation therapy until recurrence may result in worse visual and endocrine function

Superior Verbal Learning and Memory in Pediatric Brain Tumor Survivors Treated With Proton Versus Photon Radiotherapy

OBJECTIVE: Radiotherapy for pediatric brain tumor has been associated with late cognitive effects. Compared to conventional photon radiotherapy (XRT), proton radiotherapy (PRT) delivers lower doses of radiation to healthy brain tissue. PRT has been associated with improved long-term cognitive outcomes compared to XRT. However, there is limited research comparing the effects of XRT and PRT on verbal memory. METHOD: Survivors of pediatric brain tumor treated with either XRT ( RESULTS: Overall, patients receiving PRT demonstrated superior verbal learning and recall compared to those treated with XRT. Encoding and retrieval deficits were more common in the XRT group than the PRT group, with encoding problems being most prevalent. The PRT group was more likely to engage in semantic clustering strategies, which predicted better encoding and retrieval. Encoding ability was associated with higher intellectual and adaptive functioning, and fewer parent-reported concerns about day-to-day attention and cognitive regulation. CONCLUSION: Results suggest that PRT is associated with verbal memory sparing, driven by effective encoding and use of learning strategies. Future work may help to clarify underlying neural mechanisms associated with verbal memory decline, which will better inform treatment approaches

Clinical, radiologic, pathologic, and molecular characteristics of long-term survivors of diffuse intrinsic pontine glioma (DIPG): a collaborative report from the International and European Society for Pediatric Oncology DIPG registries

Purpose Diffuse intrinsic pontine glioma (DIPG) is a brainstem malignancy with a median survival of &lt; 1 year. The International and European Society for Pediatric Oncology DIPG Registries collaborated to compare clinical, radiologic, and histomolecular characteristics between short-term survivors (STSs) and long-term survivors (LTSs). Materials and Methods Data abstracted from registry databases included patients from North America, Australia, Germany, Austria, Switzerland, the Netherlands, Italy, France, the United Kingdom, and Croatia. Results Among 1,130 pediatric and young adults with radiographically confirmed DIPG, 122 (11%) were excluded. Of the 1,008 remaining patients, 101 (10%) were LTSs (survival ≥ 2 years). Median survival time was 11 months (interquartile range, 7.5 to 16 months), and 1-, 2-, 3-, 4-, and 5-year survival rates were 42.3% (95% CI, 38.1% to 44.1%), 9.6% (95% CI, 7.8% to 11.3%), 4.3% (95% CI, 3.2% to 5.8%), 3.2% (95% CI, 2.4% to 4.6%), and 2.2% (95% CI, 1.4% to 3.4%), respectively. LTSs, compared with STSs, more commonly presented at age &lt; 3 or &gt; 10 years (11% v 3% and 33% v 23%, respectively; P &lt; .001) and with longer symptom duration ( P &lt; .001). STSs, compared with LTSs, more commonly presented with cranial nerve palsy (83% v 73%, respectively; P = .008), ring enhancement (38% v 23%, respectively; P = .007), necrosis (42% v 26%, respectively; P = .009), and extrapontine extension (92% v 86%, respectively; P = .04). LTSs more commonly received systemic therapy at diagnosis (88% v 75% for STSs; P = .005). Biopsies and autopsies were performed in 299 patients (30%) and 77 patients (10%), respectively; 181 tumors (48%) were molecularly characterized. LTSs were more likely to harbor a HIST1H3B mutation (odds ratio, 1.28; 95% CI, 1.1 to 1.5; P = .002). Conclusion We report clinical, radiologic, and molecular factors that correlate with survival in children and young adults with DIPG, which are important for risk stratification in future clinical trials

Cognitive Sparing in Proton versus Photon Radiotherapy for Pediatric Brain Tumor Is Associated with White Matter Integrity: An Exploratory Study

Radiotherapy for pediatric brain tumors is associated with reduced white matter structural integrity and neurocognitive decline. Superior cognitive outcomes have been reported following proton radiotherapy (PRT) compared to photon radiotherapy (XRT), presumably due to improved sparing of normal brain tissue. This exploratory study examined the relationship between white matter change and late cognitive effects in pediatric brain tumor survivors treated with XRT versus PRT. Pediatric brain tumor survivors treated with XRT

Silencing BMI1 eliminates tumor formation of pediatric glioma CD133+ cells not by affecting known targets but by down-regulating a novel set of core genes

Abstract Clinical outcome of children with malignant glioma remains dismal. Here, we examined the role of over-expressed BMI1, a regulator of stem cell self-renewal, in sustaining tumor formation in pediatric glioma stem cells. Our investigation revealed BMI1 over-expression in 29 of 54 (53.7%) pediatric gliomas, 8 of 8 (100%) patient derived orthotopic xenograft (PDOX) mouse models, and in both CD133+ and CD133− glioma cells. We demonstrated that lentiviral-shRNA mediated silencing of suppressed cell proliferation in vitro in cells derived from 3 independent PDOX models and eliminated tumor-forming capacity of CD133+ and CD133− cells derived from 2 PDOX models in mouse brains. Gene expression profiling showed that most of the molecular targets of BMI1 ablation in CD133+ cells were different from that in CD133- cells. Importantly, we found that silencing BMI1 in CD133+ cells derived from 3 PDOX models did not affect most of the known genes previously associated with the activated BMI1, but modulated a novel set of core genes, including RPS6KA2, ALDH3A2, FMFB, DTL, API5, EIF4G2, KIF5c, LOC650152, C20ORF121, LOC203547, LOC653308, and LOC642489, to mediate the elimination of tumor formation. In summary, we identified the over-expressed BMI1 as a promising therapeutic target for glioma stem cells, and suggest that the signaling pathways associated with activated BMI1 in promoting tumor growth may be different from those induced by silencing BMI1 in blocking tumor formation. These findings highlighted the importance of careful re-analysis of the affected genes following the inhibition of abnormally activated oncogenic pathways to identify determinants that can potentially predict therapeutic efficacy.http://deepblue.lib.umich.edu/bitstream/2027.42/110124/1/40478_2014_Article_160.pd

Results of Treatment for Patients With Multicentric or Bilaterally Predisposed Unilateral Wilms Tumor (AREN0534): A report from the Children’s Oncology Group

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156248/2/cncr32958_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156248/1/cncr32958.pd